As an ink-jet recording apparatus used as an image recording apparatus or an image forming apparatus such as a printer, a facsimile machine or a copier and a liquid droplet discharging head, the following configurations are known. The configurations include a nozzle that discharges ink and a pressurization chamber. The pressurization chamber is also called an ink passage, a pressurization liquid chamber, a pressure chamber, a discharging chamber, a liquid chamber or such, and communicates with the nozzle. The configuration further includes an elecromechanical transducing device such as a piezoelectric element pressurizing the ink in the pressurization chamber or an electrothermal element such as a heater, a vibration plate used as a wall of the ink passage, and an energy generation part including an electrode that faces the vibration plate. In this configuration, the ink is pressurized by energy generated by the energy generation part and an ink droplet is discharged from the nozzle.
As the ink-jet recording head, two types have been put into practice. One type uses a piezoelectric actuator of a longitudinal oscillation mode which expands and shrinks in an axial direction of a piezoelectric element. The other type uses a piezoelectric actuator of a flexural oscillation mode. As an ink-jet recording head using the actuator of the flexural oscillation mode, the following one, for example, is known. In the ink-jet recording head, a uniform piezoelectric material layer is formed by a deposition (film forming) technique through the entire surface of a vibration plate, the piezoelectric material layer is scribed into shapes corresponding to pressure generation chambers by a lithography method and piezoelectric elements are formed in such a manner that the respective pressure generation chambers are separated from each other.
However, in the lithography method, an efficiency of using material may be low, and processes may be complicated. Therefore, a high cost may be required and a tact time may be long. In particular, a film thickness of micrometers is required for the piezoelectric material layer. Therefore, forming a fine pattern by a printing method has been studied for the purpose of reducing the cost. For example, a technique has been introduced in which a fine pattern is formed by a printing technique such as an ink-jet method on a pattern substrate on which water repellent and hydrophilic treatment is carried out on the lower layer (for example, see Japanese Laid-Open Patent Applications Nos. 2004-006645 and 2005-327920).
However, in this case, almost all configurations are such that a metallic electrode in which mostly Pt is used as a base is used as a lower electrode, and a guarantee for fatigue characteristics of PZT that is a typical material as the piezoelectric material layer may be worried about. Specifically, degradation of fatigue characteristics caused by diffusion of Pb included in PZT may be worried about. For this point, it has been disclosed that fatigue characteristics of PZT are improved by using an oxide electrode (see Japanese Patent No. 3019845).
However, in a case where an oxide electrode is used, the specific resistance is higher than a metal electrode by approximately 10 through 1000 times. Therefore, when an oxide electrode is provided in common for plural piezoelectric elements, voltage drops occur in a case where many ink droplets are discharged at once as a result of the plural piezoelectric elements being driven. Thus, displacement amounts of the piezoelectric elements may become unstable, and thus, it may not be possible to obtain stable ink discharging characteristics.